[INFO] fetching crate rustc-hex 2.1.0...
[INFO] checking rustc-hex-2.1.0 against master#7b3a7819371cef92a187e9bac8f7810ccde15216 for pr-74846
[INFO] extracting crate rustc-hex 2.1.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate rustc-hex 2.1.0 on toolchain 7b3a7819371cef92a187e9bac8f7810ccde15216
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rustc-hex 2.1.0
[INFO] finished tweaking crates.io crate rustc-hex 2.1.0
[INFO] tweaked toml for crates.io crate rustc-hex 2.1.0 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d4a5c4c6cebd17164f82c39e80e2b112bfc7d33083cf951f41e8361dc892648a
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "d4a5c4c6cebd17164f82c39e80e2b112bfc7d33083cf951f41e8361dc892648a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d4a5c4c6cebd17164f82c39e80e2b112bfc7d33083cf951f41e8361dc892648a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d4a5c4c6cebd17164f82c39e80e2b112bfc7d33083cf951f41e8361dc892648a", kill_on_drop: false }`
[INFO] [stdout] d4a5c4c6cebd17164f82c39e80e2b112bfc7d33083cf951f41e8361dc892648a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+7b3a7819371cef92a187e9bac8f7810ccde15216" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 66b72bba3505f68bb1a8e7b3b43a8b0224132ab95756d4c6fb411cd2b676388e
[INFO] running `Command { std: "docker" "start" "-a" "66b72bba3505f68bb1a8e7b3b43a8b0224132ab95756d4c6fb411cd2b676388e", kill_on_drop: false }`
[INFO] [stderr]     Checking rustc-hex v2.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]   --> benches/hex.rs:14:22
[INFO] [stdout]    |
[INFO] [stdout] 14 |         s.as_bytes().to_hex();
[INFO] [stdout]    |                      ^^^^^^ cannot infer type for type parameter `T` declared on the associated function `to_hex`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `_: std::iter::FromIterator<char>`
[INFO] [stdout] help: consider specifying the type argument in the method call
[INFO] [stdout]    |
[INFO] [stdout] 14 |         s.as_bytes().to_hex::<T>();
[INFO] [stdout]    |                            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rustc-hex`.
[INFO] [stdout] error[E0282]: type annotations needed
[INFO] [stdout]   --> benches/hex.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let sb = s.as_bytes().to_hex();
[INFO] [stdout]    |         -- consider giving `sb` a type
[INFO] [stdout] 24 |     b.iter(|| {
[INFO] [stdout] 25 |         sb.from_hex().unwrap();
[INFO] [stdout]    |         ^^ cannot infer type
[INFO] [stdout]    |
[INFO] [stdout]    = note: type must be known at this point
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] warning: unused import: `FromHex`
[INFO] [stdout]  --> benches/hex.rs:7:11
[INFO] [stdout]   |
[INFO] [stdout] 7 | use hex::{FromHex, ToHex};
[INFO] [stdout]   |           ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0282, E0283.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0282`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "66b72bba3505f68bb1a8e7b3b43a8b0224132ab95756d4c6fb411cd2b676388e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66b72bba3505f68bb1a8e7b3b43a8b0224132ab95756d4c6fb411cd2b676388e", kill_on_drop: false }`
[INFO] [stdout] 66b72bba3505f68bb1a8e7b3b43a8b0224132ab95756d4c6fb411cd2b676388e